Morphine and blood test

How long does it take for morphine not to show up on a blood test? I know erowid says the piss test is 84 hrs and i'm only at 47hrs as of now... just halfway there and a little more. I did about 120mg for three or four days in a row (snorted it) and i just did have a drug test today about 2 hrs ago. I tried putting the recommended amount of bleach in my sample, but i'm not too confident that will work since they can test for ph, oxidants, and whatnot. The conditions of this are that if I come up positive I am kicked out of the house. I called the nurse over at the shrink's office and asked her to call me and not the home phone with the results, but i don't know if i trust her.

Anyways, she told me that if I have a positive on this piss test then I can come in and do a blood test instead. How long do I have to get this shit outta me and how can I do it in about 4-5 days??? Any ideas???